NASHVILLE — Senate Republicans on Wednesday delayed approval of $572.7 million for transportation projects, a plan pushed by the Bredesen administration.

The Senate Finance Committee move came as Senate Majority Leader Mark Norris, R-Collierville, grilled state Transportation Commissioner Gerald Nicely for details on what money will fund which bridge and road projects under Gov. Phil Bredesen’s proposed “three-tiered” plan for transportation.

“We’re sort of in the dark about that,” Sen. Norris told Mr. Nicely.

State Finance Commissioner Dave Goetz agreed to a delay until Monday as Republicans seek further details.

Gov. Bredesen wants to issue $350 million in state bonds to fund repair or replacement of an estimated 200 of the state’s 300 structurally deficient bridges.

But the general obligation bonds, which would use federal bridge funds over the next 12 years, have drawn opposition from Republicans, including Lt. Gov. Ron Ramsey, R-Blountville. The other parts of funding include federal stimulus dollars and regular state and federal spending on construction.

Sen. Norris also questioned why the administration was pressing for authority to spend the federal transportation money through the fast-moving expansion request process instead of a supplemental budget that allows for more scrutiny by lawmakers.

Mr. Nicely said he had no specific details to provide details Wednesday on what pot of money was paying for which project. The administration has used a “comprehensive approach” in formulating how it will use stimulus funds, regular state and federal spending and the bonds, he said. But he also said each pot of money and the projects they fund can stand on their own if necessary.

He said the speedier expansion request process is needed to spend the money in the current budget year. The state is “under a tight timeframe,” said Mr. Nicely, who wants to let bids on stimulus-related projects before July 1.

Sen. Bo Watson, R-Hixson, a Finance Committee member, later said he agreed with the need for delay.

“I think he (Sen. Norris) just wanted more time to figure out how the puzzle fits together” among stimulus-funded projects, bonded projects and regularly funded projects, he said. “I don’t think there’s an opposition to the stimulus money.”

Mr. Nicely said after the meeting, “If we stall this, we’ll wind up getting behind other states that were moving ahead very aggressively. We had been moving very well until now.”